function md5(string) {
  function md5_RotateLeft(lValue, iShiftBits) {
    return (lValue << iShiftBits) | (lValue >>> (32 - iShiftBits));
  }
  function md5_AddUnsigned(lX, lY) {
    let lX4,
      lY4,
      lX8,
      lY8,
      lResult;
    lX8 = (lX & 0x80000000);
    lY8 = (lY & 0x80000000);
    lX4 = (lX & 0x40000000);
    lY4 = (lY & 0x40000000);
    lResult = (lX & 0x3FFFFFFF) + (lY & 0x3FFFFFFF);
    if (lX4 & lY4) {
      return (lResult ^ 0x80000000 ^ lX8 ^ lY8);
    }
    if (lX4 | lY4) {
      if (lResult & 0x40000000) {
        return (lResult ^ 0xC0000000 ^ lX8 ^ lY8);
      }
      return (lResult ^ 0x40000000 ^ lX8 ^ lY8);
    }
    return (lResult ^ lX8 ^ lY8);
  }
  function md5_F(x, y, z) {
    return (x & y) | ((~x) & z);
  }
  function md5_G(x, y, z) {
    return (x & z) | (y & (~z));
  }
  function md5_H(x, y, z) {
    return (x ^ y ^ z);
  }
  function md5_I(x, y, z) {
    return (y ^ (x | (~z)));
  }
  function md5_FF(a, b, c, d, x, s, ac) {
    a = md5_AddUnsigned(a, md5_AddUnsigned(md5_AddUnsigned(md5_F(b, c, d), x), ac));
    return md5_AddUnsigned(md5_RotateLeft(a, s), b);
  }
  function md5_GG(a, b, c, d, x, s, ac) {
    a = md5_AddUnsigned(a, md5_AddUnsigned(md5_AddUnsigned(md5_G(b, c, d), x), ac));
    return md5_AddUnsigned(md5_RotateLeft(a, s), b);
  }
  function md5_HH(a, b, c, d, x, s, ac) {
    a = md5_AddUnsigned(a, md5_AddUnsigned(md5_AddUnsigned(md5_H(b, c, d), x), ac));
    return md5_AddUnsigned(md5_RotateLeft(a, s), b);
  }
  function md5_II(a, b, c, d, x, s, ac) {
    a = md5_AddUnsigned(a, md5_AddUnsigned(md5_AddUnsigned(md5_I(b, c, d), x), ac));
    return md5_AddUnsigned(md5_RotateLeft(a, s), b);
  }
  function md5_ConvertToWordArray(string) {
    let lWordCount;
    const lMessageLength = string.length;
    const lNumberOfWords_temp1 = lMessageLength + 8;
    const lNumberOfWords_temp2 = (lNumberOfWords_temp1 - (lNumberOfWords_temp1 % 64)) / 64;
    const lNumberOfWords = (lNumberOfWords_temp2 + 1) * 16;
    const lWordArray = Array(lNumberOfWords - 1);
    let lBytePosition = 0;
    let lByteCount = 0;
    while (lByteCount < lMessageLength) {
      lWordCount = (lByteCount - (lByteCount % 4)) / 4;
      lBytePosition = (lByteCount % 4) * 8;
      lWordArray[lWordCount] = (lWordArray[lWordCount] | (string.charCodeAt(lByteCount) << lBytePosition));
      lByteCount++;
    }
    lWordCount = (lByteCount - (lByteCount % 4)) / 4;
    lBytePosition = (lByteCount % 4) * 8;
    lWordArray[lWordCount] = lWordArray[lWordCount] | (0x80 << lBytePosition);
    lWordArray[lNumberOfWords - 2] = lMessageLength << 3;
    lWordArray[lNumberOfWords - 1] = lMessageLength >>> 29;
    return lWordArray;
  }
  function md5_WordToHex(lValue) {
    let WordToHexValue = "",
      WordToHexValue_temp = "",
      lByte,
      lCount;
    for (lCount = 0; lCount <= 3; lCount++) {
      lByte = (lValue >>> (lCount * 8)) & 255;
      WordToHexValue_temp = `0${lByte.toString(16)}`;
      WordToHexValue += WordToHexValue_temp.substr(WordToHexValue_temp.length - 2, 2);
    }
    return WordToHexValue;
  }
  function md5_Utf8Encode(string) {
    string = string.replace(/\r\n/g, "\n");
    let utftext = "";
    for (let n = 0; n < string.length; n++) {
      const c = string.charCodeAt(n);
      if (c < 128) {
        utftext += String.fromCharCode(c);
      } else if ((c > 127) && (c < 2048)) {
        utftext += String.fromCharCode((c >> 6) | 192);
        utftext += String.fromCharCode((c & 63) | 128);
      } else {
        utftext += String.fromCharCode((c >> 12) | 224);
        utftext += String.fromCharCode(((c >> 6) & 63) | 128);
        utftext += String.fromCharCode((c & 63) | 128);
      }
    }
    return utftext;
  }
  let x = Array();
  let k,
    AA,
    BB,
    CC,
    DD,
    a,
    b,
    c,
    d;
  let S11 = 7,
    S12 = 12,
    S13 = 17,
    S14 = 22;
  let S21 = 5,
    S22 = 9,
    S23 = 14,
    S24 = 20;
  let S31 = 4,
    S32 = 11,
    S33 = 16,
    S34 = 23;
  let S41 = 6,
    S42 = 10,
    S43 = 15,
    S44 = 21;
  string = md5_Utf8Encode(string);
  x = md5_ConvertToWordArray(string);
  a = 0x67452301; b = 0xEFCDAB89; c = 0x98BADCFE; d = 0x10325476;
  for (k = 0; k < x.length; k += 16) {
    AA = a; BB = b; CC = c; DD = d;
    a = md5_FF(a, b, c, d, x[k + 0], S11, 0xD76AA478);
    d = md5_FF(d, a, b, c, x[k + 1], S12, 0xE8C7B756);
    c = md5_FF(c, d, a, b, x[k + 2], S13, 0x242070DB);
    b = md5_FF(b, c, d, a, x[k + 3], S14, 0xC1BDCEEE);
    a = md5_FF(a, b, c, d, x[k + 4], S11, 0xF57C0FAF);
    d = md5_FF(d, a, b, c, x[k + 5], S12, 0x4787C62A);
    c = md5_FF(c, d, a, b, x[k + 6], S13, 0xA8304613);
    b = md5_FF(b, c, d, a, x[k + 7], S14, 0xFD469501);
    a = md5_FF(a, b, c, d, x[k + 8], S11, 0x698098D8);
    d = md5_FF(d, a, b, c, x[k + 9], S12, 0x8B44F7AF);
    c = md5_FF(c, d, a, b, x[k + 10], S13, 0xFFFF5BB1);
    b = md5_FF(b, c, d, a, x[k + 11], S14, 0x895CD7BE);
    a = md5_FF(a, b, c, d, x[k + 12], S11, 0x6B901122);
    d = md5_FF(d, a, b, c, x[k + 13], S12, 0xFD987193);
    c = md5_FF(c, d, a, b, x[k + 14], S13, 0xA679438E);
    b = md5_FF(b, c, d, a, x[k + 15], S14, 0x49B40821);
    a = md5_GG(a, b, c, d, x[k + 1], S21, 0xF61E2562);
    d = md5_GG(d, a, b, c, x[k + 6], S22, 0xC040B340);
    c = md5_GG(c, d, a, b, x[k + 11], S23, 0x265E5A51);
    b = md5_GG(b, c, d, a, x[k + 0], S24, 0xE9B6C7AA);
    a = md5_GG(a, b, c, d, x[k + 5], S21, 0xD62F105D);
    d = md5_GG(d, a, b, c, x[k + 10], S22, 0x2441453);
    c = md5_GG(c, d, a, b, x[k + 15], S23, 0xD8A1E681);
    b = md5_GG(b, c, d, a, x[k + 4], S24, 0xE7D3FBC8);
    a = md5_GG(a, b, c, d, x[k + 9], S21, 0x21E1CDE6);
    d = md5_GG(d, a, b, c, x[k + 14], S22, 0xC33707D6);
    c = md5_GG(c, d, a, b, x[k + 3], S23, 0xF4D50D87);
    b = md5_GG(b, c, d, a, x[k + 8], S24, 0x455A14ED);
    a = md5_GG(a, b, c, d, x[k + 13], S21, 0xA9E3E905);
    d = md5_GG(d, a, b, c, x[k + 2], S22, 0xFCEFA3F8);
    c = md5_GG(c, d, a, b, x[k + 7], S23, 0x676F02D9);
    b = md5_GG(b, c, d, a, x[k + 12], S24, 0x8D2A4C8A);
    a = md5_HH(a, b, c, d, x[k + 5], S31, 0xFFFA3942);
    d = md5_HH(d, a, b, c, x[k + 8], S32, 0x8771F681);
    c = md5_HH(c, d, a, b, x[k + 11], S33, 0x6D9D6122);
    b = md5_HH(b, c, d, a, x[k + 14], S34, 0xFDE5380C);
    a = md5_HH(a, b, c, d, x[k + 1], S31, 0xA4BEEA44);
    d = md5_HH(d, a, b, c, x[k + 4], S32, 0x4BDECFA9);
    c = md5_HH(c, d, a, b, x[k + 7], S33, 0xF6BB4B60);
    b = md5_HH(b, c, d, a, x[k + 10], S34, 0xBEBFBC70);
    a = md5_HH(a, b, c, d, x[k + 13], S31, 0x289B7EC6);
    d = md5_HH(d, a, b, c, x[k + 0], S32, 0xEAA127FA);
    c = md5_HH(c, d, a, b, x[k + 3], S33, 0xD4EF3085);
    b = md5_HH(b, c, d, a, x[k + 6], S34, 0x4881D05);
    a = md5_HH(a, b, c, d, x[k + 9], S31, 0xD9D4D039);
    d = md5_HH(d, a, b, c, x[k + 12], S32, 0xE6DB99E5);
    c = md5_HH(c, d, a, b, x[k + 15], S33, 0x1FA27CF8);
    b = md5_HH(b, c, d, a, x[k + 2], S34, 0xC4AC5665);
    a = md5_II(a, b, c, d, x[k + 0], S41, 0xF4292244);
    d = md5_II(d, a, b, c, x[k + 7], S42, 0x432AFF97);
    c = md5_II(c, d, a, b, x[k + 14], S43, 0xAB9423A7);
    b = md5_II(b, c, d, a, x[k + 5], S44, 0xFC93A039);
    a = md5_II(a, b, c, d, x[k + 12], S41, 0x655B59C3);
    d = md5_II(d, a, b, c, x[k + 3], S42, 0x8F0CCC92);
    c = md5_II(c, d, a, b, x[k + 10], S43, 0xFFEFF47D);
    b = md5_II(b, c, d, a, x[k + 1], S44, 0x85845DD1);
    a = md5_II(a, b, c, d, x[k + 8], S41, 0x6FA87E4F);
    d = md5_II(d, a, b, c, x[k + 15], S42, 0xFE2CE6E0);
    c = md5_II(c, d, a, b, x[k + 6], S43, 0xA3014314);
    b = md5_II(b, c, d, a, x[k + 13], S44, 0x4E0811A1);
    a = md5_II(a, b, c, d, x[k + 4], S41, 0xF7537E82);
    d = md5_II(d, a, b, c, x[k + 11], S42, 0xBD3AF235);
    c = md5_II(c, d, a, b, x[k + 2], S43, 0x2AD7D2BB);
    b = md5_II(b, c, d, a, x[k + 9], S44, 0xEB86D391);
    a = md5_AddUnsigned(a, AA);
    b = md5_AddUnsigned(b, BB);
    c = md5_AddUnsigned(c, CC);
    d = md5_AddUnsigned(d, DD);
  }
  return (md5_WordToHex(a) + md5_WordToHex(b) + md5_WordToHex(c) + md5_WordToHex(d)).toLowerCase();
}

module.exports = {
  hexMD5: md5,
};
